Add support for removing empty resources from architecture

The removal part of #267.

b_asic/architecture.py

@@ -801,8 +801,28 @@ of :class:`~b_asic.architecture.ProcessingElement`
 
         if resource in self.memories:
             self.memories.remove(resource)
-        else:
+        elif resource in self.processing_elements:
             self.processing_elements.remove(resource)
+        else:
+            raise ValueError('Resource not in architecture')
+
+    def assign_resources(self, heuristic: str = "left_edge") -> None:
+        """
+        Convenience method to assign all resources in the architecture.
+
+        Parameters
+        ----------
+        heuristic : str, default: "left_edge"
+            The heurstic to use.
+
+        See Also
+        --------
+        Memory.assign
+        ProcessingElement.assign
+
+        """
+        for resource in chain(self.memories, self.processing_elements):
+            resource.assign(heuristic=heuristic)
 
     def move_process(
         self,